The invention relates to an improvement in ion detectors. More particularly, this invention relates to an improved electrical connection to the anode or cathode of an ionization chamber type of ion detector.
The presence of radioactive materials which emit beta particles during decay can be detected using an ion detection device such as an ionization chamber which detects the ionization of a gas in the chamber by beta emission. The ionization chamber comprises a gas filled housing containing an anode and a cathode to which any ionization in the gas is swept by the electric field produced by the electrodes.
Tritium, which has a half-life of 12.26 years and undergoes natural radioactive decay through beta emission at 18.6 keV maximum energy with an average energy of 5.69 keV, may be detected using such an ion detection device. Such tritium detectors are, in fact, widely used in some facilities where radioactive materials are handled.
Such detectors commonly comprises a housing having therein a central rod or tube which comprises one electrode surrounded by a hollow cylindrical jacket which forms the other electrode. Electrical connection is usually made to one or both of the electrodes by soldering wire leads to the electrode, e.g., the anode, which interconnects the anode with an external terminal on the device.
This type of electrical connection, however, creates problems. The use of a solder connection to the electrodes results in an assembly which is difficult to remove for cleaning purposes and can result in the generation of various outgas contaminants. Since the process for cleaning and reassembling the devices is potentially hazardous and must be performed in a glove-box, elimination of the solder attachment to the electrode, which would simplify cleaning and assembly of the device, would be advantageous.